JPH0615511Y2 - Flat Motor - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to a flat motor used in OA equipment such as a copying machine.

[Conventional technology]

FIG. 2 is a partially cutaway front view of a conventional flat motor. In the figure, (1) is a rear bracket made of a magnetic material, (2) is a permanent magnet fixed to the rear bracket (1), 3) is a front bracket provided with a gap in the axial direction of the permanent magnet (2), (4) is an amateur rotatably arranged between the permanent magnet (2) and the front bracket (3),
(5) is a coil built in the amateur (4), (6) is a commutator connected to the armature (4) and connected to the coil (5), (7) is an amateur (4) and a commutator (6) The rotating shaft supporting the rotating shaft, and (8) and (9) are bearings supporting the rotating shaft (7). (7a) is a gear provided in the output part of the rotary shaft. (10) is a non-magnetic base, (11) is a cover, (12) is the base (10), and bolts for fixing the cover (11) to the rear bracket (1). Reference numeral (13) is a holder for housing the brush (14), and reference numeral (15) is a spring for pressing the brush (14) against the commutator (6). The motor main body (22) is constituted by the rear bracket (1) to the spring (15) described above. (16) is rear bracket (1), front bracket (3)
With the plate fixed integrally, 17 is a shaft fixed to the plate (16) by, for example, caulking, and (18) is this shaft (17)
The output gear, which is supported by and is meshed with the gear (7a), (19)
Is a plate-like body made of, for example, a rubber material interposed between the front bracket (3) and the plate (16), and (20) fixes the rear bracket (1), the front bracket (3), and the plate (16). It is a bolt to do. The elastic body (19) has a disc shape, and one side surface is provided with several annular grooves (19a) concentrically forming a recess.

Next, the operation will be described. First, when a voltage is applied to the brush (14) from a power supply circuit (not shown), the rotating shaft (7) rotates according to Fleming's left-hand rule due to the relationship between the current flowing in the coil (5) and the magnetic flux of the permanent magnet (2). This rotation is due to the gear (7
It is transmitted to the gear (18) meshing with (a) and further transmitted to a driven system (not shown). Further, this rotation is detected by a rotation detector (not shown), and a control circuit (not shown)
The rotation is controlled by.

In addition, when the flat motor is rotating (especially during switching control), large vibration is generated at the contact part between the brush (14) and the commutator (6) or the tip part of the armature (4), and the vibration is generated. Although the entire flat motor is transmitted to each member and vibrates, the bracket formed of the plate material vibrates, which causes annoying noise.
Therefore, the elastic body (19) is interposed between the front bracket (3) and the plate (16), the vibration energy is absorbed by the elastic body (19), and the vibration velocity or the vibration amplitude is attenuated to reduce noise. Is being reduced. According to the experiment, the noise can be reduced by about 5 dB.

[Problems to be solved by the device]

In the structure configured as described above, the elastic body (19) is interposed between the front bracket (3) and the plate (16) in a deformed and compressed state.

Here, the amount of deformation of the elastic body (19) depends on the front bracket (3).
Depending on the size of the gap between the plate and the plate (16), the size of this gap will vary considerably due to manufacturing errors. Therefore, if this gap becomes smaller than the set value, the elastic body (19) will be excessively deformed beyond the set value.

However, considering the allowable deformation amount for compression of the elastic body (19), the elastic body (19) may be deformed in the direction in which the groove (19a) is narrowed at the place where the groove (19a) is formed. The amount of allowable deformation is extremely small in the area where () is not formed. Particularly, in the flat motor as described above, the thickness of the elastic body is usually about 2 to 3 mm, and since the thickness is thin, the allowable deformation amount is also small.

Therefore, when the size of the gap between the front bracket (3) and the plate (16) becomes smaller than the set value due to the manufacturing error as described above, the dimensional error is reduced by the elastic body.
It is difficult to absorb due to the deformation of (19), and elastic body
The plate (16) is pressed toward the shaft (17) and deformed by the repulsive force from the plate (19). Therefore, an error occurs in the relative positional relationship between the rotating shaft (7) and the shaft (17) (must be parallel to each other), resulting in poor meshing between the gear (7a) and the gear (18), noise, There were problems such as uneven rotation and uneven wear.

[Means for Solving the Problems]

The present invention has been made to solve the above-mentioned problems, in which a plate-shaped elastic body having concave portions alternately formed on both surfaces is provided between the plate and one bracket.

[Action]

In this invention, since the concave portions are alternately formed on both sides of the elastic body, the allowable deformation amount of the elastic body is large,
Even if the size of the gap between the front bracket and the plate varies, the dimensional error can be absorbed by the elastic member of the plate-like body made of, for example, a rubber material, and the deformation of the plate can be prevented.

〔Example〕

An embodiment of the present invention will be described below with reference to FIG.
In the figure, (21) is an elastic body of a plate-like body made of, for example, a rubber material, (21a), (21b) is an annular groove forming concentric recesses alternately on both sides of this elastic body (21), Elastic body (2
The groove (21a) or (21b) is present on both surfaces or at least one of the surfaces on the plate side at any position in the radial direction of 1). Reference numeral (21c) is a tapered rib formed at a predetermined angle with respect to both surfaces of the elastic body (21) and each surface contacting the plate. That is, the elastic body (21) has a so-called bellows shape in the radial direction.

In the above structure, the groove (21a) is formed at any position in the radial direction of the elastic body (21) with respect to the compression direction.
Alternatively, (21b) is formed, and the entire elastic body (21) is grooved.
Since (21a) or (21b) can be deformed in a narrowing direction, the allowable deformation amount becomes large. Therefore, even if the size of the gap between the front bracket (3) and the plate (16) becomes smaller than the set value due to manufacturing errors,
The dimensional error can be absorbed by the deformation of the elastic body (21), and the plate (16) is not pressed and deformed by the shaft (17) by the repulsive force from the elastic body (21). For this reason,
There is no error in the relative positional relationship between the rotating shaft (7) and the shaft (17) (must be parallel to each other), and the gear (7a)
Since the meshing between the gear and the gear (18) is also good, noise, uneven rotation, and uneven wear do not occur.

Needless to say, the elastic body (21) can reduce noise as in the conventional device.

[Effect of device]

As described above, according to this invention, it is possible to prevent noise, uneven rotation, and uneven wear, and to obtain a flat motor with stable characteristics and high reliability.

[Brief description of drawings]

FIG. 1 is a partially cutaway front view showing a flat motor according to an embodiment of the present invention, and FIG. 2 is a partially cutaway front view showing a conventional flat motor. In the figure, (1) is a rear bracket, (2) is a permanent magnet, (3) is a front bracket, (4) is an amateur, (7) is a rotating shaft, and (7
a) is a gear, (16) is a plate, (17) is a shaft, (18) is an output gear, (21) is an elastic body, (21a) and (21b) are grooves, and (22) is a motor body. is there. In the drawings, the same reference numerals indicate the same or corresponding parts.

Claims (1)

[Scope of utility model registration request] 1. A flat motor comprising a motor body (22), a plate (16), an output gear (18), and an elastic body (21), wherein the elastic body (21) has both sides. The plate (16) is attached to one bracket (3) of the motor body (22) with the elastic body (21) sandwiched between the plate (16) and the plate (16) for output. The gear (18) is meshed with the gear (7a) provided on the output part of the rotary shaft (7) of the motor body (22) to form the plate (16).
A flat motor that is rotatably supported by.